Machine frame for typewriters



Sept. 29, 1942. J. U E I 2,297,229

MACHINE FRAME FOR TYPEWRITERS Filed April -29, 1959 Patented Sept. 29, 1942 r MACHINE FRAME FOR TYPEWRITERS Johannes Kriiger, Erfurt, Germany; vested in the Alien Property Custodian Application April 29, 1939, Serial No. 270,843 In Germany April 29, 1938 4 Claims.

This invention relates to typewriters and particularly to frame constructions for typewriters in which the carriage and type mechanism is mounted on an inner skeleton frame which is thereafter covered by an outer decorative frame or cover.

Frames or covers for this class of typewriters have usually been constructed of sectional parts which are assembled together on the inner frame or attached to an auxiliary outer skeleton frame. Such covering frames as usually constructed cannot be formed as an integral unit as is desirable for efficient mass production by pressing operations. Also in covering frames wherein an attempt has been made to make as much as possible in one piece and in which some parts, for instance the rear wall covering parts, are separately attached, it is necessary to remove the paper carriage and in some instances, with long carriages, the carriage guides before applying the finish covering. These operations are tedious, especially with ball bearing carriage mounts, and also any work on the machine after applying the finish covering is undesirable because of the likelihood of scratching or damaging the finish of the protective outer covering frame.

It is the object of the present invention to overcome these and other disadvantages by providing an outer cover or frame formed as an integral unit and an inner skeleton frame carrying the type mechanism and paper carriage which may he slipped into the cover frame after being completely assembled.

The outer frame or cover according to the invention comprises integral side members and front and rear cross members with a unitary vertical and horizontal wall portion extending between the upperportions of the sides intermediate the ends thereof defining a rectangular opening for the key assembly between the vertical wall and the front cross member and an open space between the rear edge of the horizontal wall portion and the rear cross member through which the skeleton frame with all parts assembled thereon can be inserted endwise from above on an inclined path and then be moved to final seating position by raising the front end relative to the cover frame.

In typewriting machines according to the invention, it is not possible to slide the cover or mask over the completely assembled mechanism on the inner frame because the paper carriage and guides therefor extend beyond the sides of the frame and mask. Since a unitary mask according to the invention must have a snug fit 55 with the sides of the frame, manipulation of the mask to pass it over the paper carriage is impossible so that the construction must be such that the completely assembled machine can be inserted from the top if the frames are to be assembled after the paper carriage and guides are mounted in operative position.

It is also an object of the invention to provide improved finish appearance and reinforcement of the front end portion of the cover frame by continuing the vertical intermediate wall portion forwardly along the sides in the form of an inturned flange or rib integral with the sides of the frame and forming an acute angle therewith.

Other objects and advantages of the invention will be apparent from the following detailed description taken with the accompanying drawing which illustrate a preferred constructional example of the invention and in which:

Fig. l is a perspective view of a cover frame embodying the invention,

Fig. 2 is a disjointed view, with parts in section, illustrating the manner of inserting the assembled typewriter on the skeleton frame into the cover frame, and

Fig. 3 is a fragmentary sectional view on the line 33 of Fig. 2.

The inner typewriter mechanism, as shown in Fig. 2 comprises a skeleton frame including a base, preferably in the form of a rectangular plate 5, on which the usual typewriter parts are mounted, such as the key levers 6, paper carriage 1 with its roller 8, ball bearing carriage guide 9, ink ribbon mechanism Ill and type case H. The working parts of the typewriter, which will require no further detailed description, are completely assembled on the base plate 5 before insertion into the cover frame I2.

The cover frame l2 which is preferably formed in one piece of artificial resin by a pressing or molding operation comprises spaced vertically disposed side walls l3 extending from front to rear of the frame and varying in height in conformance with the outline of the assembled typewriter unit to be mounted therein. The side walls I3 merge at their front ends with the ends of a front unitary cross wall I4 and at their rear ends into the ends of a rear unitary cross wall l5.

Intermediate the front and rear walls, the side walls 13 are connected by a reinforcing cross connection member of angular cross-section and comprising a vertical web or flange it which merges at its upper edge with a horizontal web or flange ii. The vertical web or flange .I6 is positioned so as to be disposed between the rear row of keys I8 and the type case I! when the parts are fully assembled, serving as a front cover plate for the type case, and the web I! extends rearwardly from the upper edge of the web Hi to serve as a top cover plate for the type case H and adjacent parts.

The cross connecting vertical web or flange l6 merges at its ends with inwardly turned flanges I9 integral with the upper edges of the forward portions of the side walls and forming a downwardly opening V-joint therewith, the flanges 19 serving as reinforcing ribs and defining the sides of the keyboard opening 20, the rear edge of which is defined by the Wall [6 and the front edge of which is defined by a rearwardlydi-rected flange portion 2] of the front cross wall 14. The flange portion 2| merges at its ends with the forward ends of the inturned side flanges l9, as clearly appears in Figs. 1 and 2.

The horizontal web or flange ll of the intermediate cross connection member is formed at the ends of the rear portion thereof as a cover for the ink ribbon mechanism and merges with the upper plane of the ribbon roller cover members 22.

The cover flange portion I1 is dimensioned and its rear edge is formed in relation to the rear cross wall l so as to leave an open space 23 of' sufficient area and proper shape to permit passage of the assembled typewriter unit in the inclined direction shown in Fig. 2.

For the purpose of providing reinforcement of the side and end walls and also to provide side seating points for the skeleton frame 5 of the inserted unit, the side and end walls are formed with vertical ribs 24. These ribs, seating against the sides of the skeleton frame serve to properly locate the typewriter unit in the cover frame and may easily be repaired if they become worn, broken or otherwise damaged.

The base plate 5 of the inner skeleton frame is provided with a vertical edge flange or wall 25 extending along all four sides thereof which provides a large flat bearing surface for engaging the face of the ribs 24 when the unit is seated in the cover frame. In order to dampen vibration noises and to cushion the mounting of the typewriter unit in the cover frame, cushioning strips 26 of felt or the like may be provided on the face of the walls 25 and also on the under surface thereof. By dimensioning the contacting surfaces of the two frames so as to provide a snug fit, the use of screws or bolts to fasten the one to the other is unnecessary and any possibility of warping the inner frame by unequal stresses is thereby avoided.

The inner skeleton frame and typewriter unit is inserted into the cover frame through the rear open space 23, with the keyboard end foremost, as indicated in Fig. 2, until the projecting carriage parts nearly strike the side walls I3 of the cover frame, then the forward end of the unit is elevated as will be readily understood until the keys 18 are disposed in the open space [9, the vertical cross wall I6 entering between the rear row of keys and the type case ll. At the same time, the rear end of the inserted unit is dropped down until the lower edges of both frames are in alinement, whereupon the vertical flanges of the skeleton frame will be engaged on all sides with the ribs 24. The frames are secured in assembled position by a bottom plate 2! which forms a base for the entire assembly, the base being secured to the inner skeleton frame 5 by means of screws 28 and to the outer covering frame by screws 29. Suitable rubber feet 30 are preferably provided and these may be secured in place by the screws 29, or if desired, may be attached directly to the inner frame 5, being clamped into suitable sockets therein, or otherwise. When the rubber feet are attached directly to the inner frame, a separate base plate may be omitted and the two frames may be fastened together with screws or other suitable securing means.

In order to shorten the overall length of the outer cover frame, the reinforcing flange 2| of the front wall M, which defines the front of the keyboard opening, is provided with openings 3| through which the shanks 32 of the tabulator and spacing keys can be passed, the heads of these keys being removed to permit insertion of the shanks through the openings when assembling the frames together.

Due to the complete reinforcement of the cover frame by the rib and flange constructions shown and described, the walls can be made very thin without unduly weakening the frame, thereby resulting in a saving of material and facilitating the molding and pressing in the manufacture thereof. Also, by reason of the practically continuous contact between the wall flange of the inner frame with adjacent parts of the cover frame, the latter is in effect backed up and prevented from being broken by bending forces against the sides which may arise due to rough handling of the typewriter in use or transportation. Also, by providing for a onepiece molded construction of the cover frame, many possibilities for an attractive appearance are presented and all joints which otherwise would catch dust and dirt are eliminated. Further due to the provision for a light molded or pressed unit which may be economically produced by mass production methods, in case the outer frame does get broken or marred by unduly rough handling or otherwise, it may be readily replaced at small cost and with very little labor.

While the outer covering frame has been described as being made of artificial resin it could as well be constructed of light cast metal such as magnesium or may be stamped 0r pressed from sheet metal. In any case, the relative parts can be well rounded without joints and can be made in a variety of shapes as taste demands.

Although a preferred constructional embodiment of the invention has been shown and described by way of illustration, it will be understood that modifications in the: details of construction and arrangement of the parts may be made and that other materials and methods of manufacture may be employed in the production thereof without departing from the spirit of the invention within the scope of the appended claims.

I claim:

1. In a typewriter of the type including an inner skeleton frame on which the operative mechanism of the machine is mounted, an outer cover frame unit surrounding the inner frame and adapted for assembly with the inner frame after the mounting of the operative mechanism thereon, said cover frame unit comprising unitary side, front and rear walls and an integral bridge member extending between the upper edges of the side walls intermediate the front and rear walls, said bridge member being of angular cross section and including a front vertical wall portion and an integral horizontal Wall portion extending rearwardly from the upper edge of said vertical wall portion, there being an open space between said front vertical wall portion of said bridge member and said front wall of said cover frame unit to accommodate the keyboard of the typewriter mechanism and an open space between the rear edge of said horizontal wall portion and the rear wall of said cover frame unit dimensioned to permit the endwise insertion of the skeleton frame with said typewriter mechanism assembled thereon into said cover frame unit on an inclined path from above to a position to permit the front end of said skeleton frame to be then raised to dispose the keyboard in the space in front of said vertical wall portion of said bridge member.

2. In a typewriter of the type including an inner skeleton frame on which the operative mechanism of the machine is mounted, an outer cover frame unit surrounding the inner frame and adapted for assembly with the inner frame after the mounting of the operative mechanism thereon, said cover frame unit comprising unitary side, front and rear walls and an integral bridge member extending between the upper edges of the side walls intermediate the front and rear Walls, said bridge member being of angular cross section and including a front vertical wall portion and an integral horizontal wall portion extending rearwardly from the upper edge of said vertical wall portion, said side walls from said bridge member to said front wall having integral inturned flanges at the upper edges thereof united at the rear ends thereof with the ends of said vertical wall portion of said bridge member and with said vertical wall portion and the front wall of said cover frame unit defining an open space to accommodate the keyboard of the operative mechanism, the rear edge of said horizontal wall portion being formed in relation to the rear wall of said cover frame unit to provide an open space for the endwise insertion of the skeleton frame and operative mechanism mounted thereon on an inclined path from above to a position to permit the front end of said skeleton frame to be thereafter elevated to dispose the keyboard of said mechanism in the space provided therefor.

3. In a typewriter according to claim 1, said inner skeleton frame having a peripheral wall portion and said cover frame having a plurality of vertical ribs formed on the inner face of the side and end walls thereof for engaging the peripheral wall of said skeleton frame when the two frames are in assembled relation.

4. In a typewriter according to claim 2, said inner skeleton frame having a peripheral wall portion and said cover frame having a plurality of vertical ribs formed on the inner face of the side and end walls thereof for engaging the peripheral wall of said skeleton frame when the two frames are in assembled relation.

JOI-IANNES KRi'IGER. 

